One of the original 9 members. Had a slow start, but gradually built her character up which was soon to be known as the "devil idol" because of her upright honesty and sharp mouth, though generally she just took the freedom of doing and saying whatever she felt like.

She was also the first member to officially graduate from the group due to health problems, although the shocking news didn't make it to the fan-sama until the actual day of the group's 4th concert on 2009/01/18. She's an agency senior to Miyake and Hashimoto.

Erina and Saya-nee were discussing about visiting some power spots and Zumi came up in the conversation as Saya-nee just had a strange phone call with her recently about evil spirits. It really makes you wonder what she's up to recently, though...